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The canid genus Lycalopex comprises six recently diversified South American species whose evolutionary relationships have been remarkably challenging to resolve. We analyzed 6000 bp of mitochondrial DNA (mtDNA) from 55 Lycalopex individuals (L. sechurae = 4, L. culpaeus = 7, L.griseus = 8, L.gymnocercus = 17, L.vetulus = 13 and L. fulvipes = 6), and nine specimens from the closely related species Cerdocyon thous, Chrysocyon brachyurus and Speothos venaticus, to reconstruct their phylogenetic relationships, estimate the support for species-level monophyly, and date their divergences. In addition, we also sequenced seven nuclear segments from the same taxa. Three different phylogenetic approaches converged on the same mitochondrial topology with strong support for most nodes. All species were confirmed to be monophyletic for mtDNA, except for one intriguing case in which two L. vetulus individuals carried L. gymnocercus haplotypes, potentially implying a case of interspecies admixture. L. vetulus was the first species to diverge (ca. 1.2 Mya), followed by L. sechurae and then L. gymnocercus. The most internal group comprised L. griseus and the sister-species L. culpaeus and L. fulvipes, which diverged around 430,000 years ago in southern Argentina or Chile. The analysis of nuclear markers revealed several examples of intra-specific variation coupled with lack of species monophyly, consistent with pervasive incomplete lineage sorting and/or hybridization in this recent radiation. Our results provide robust mitochondrial resolution of this challenging radiation, and illustrate the difficulty of attaining similar success with traditional nuclear markers. [ABSTRACT FROM AUTHOR]

Human transformation of natural habitats facilitates pathogen transmission between domestic and wild species. The guigna (Leopardus guigna), a small felid found in Chile, has experienced habitat loss and an increased probability of contact with domestic cats. Here, we describe the interspecific transmission of feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) between domestic cats and guignas and assess its correlation with human landscape perturbation. Blood and tissue samples from 102 free‐ranging guignas and 262 domestic cats were collected and analyzed by PCR and sequencing. Guigna and domestic cat FeLV and FIV prevalence were very similar. Phylogenetic analysis showed guigna FeLV and FIV sequences are positioned within worldwide domestic cat virus clades with high nucleotide similarity. Guigna FeLV infection was significantly associated with fragmented landscapes with resident domestic cats. There was little evidence of clinical signs of disease in guignas. Our results contribute to the understanding of the implications of landscape perturbation and emerging diseases. [ABSTRACT FROM AUTHOR]

Abstract: Since 1994 wild vicuñas have been captured and shorn for their wool, yet, there remains a noticeable lack of data regarding the possible influence of capture and shearing upon vicuña biology. Therefore, we assessed post-capture group composition, genetic relatedness, and paternity among animals that were captured for live shearing and release. We captured twenty-six groups (134 animals) on the Chilean Altiplano. Seventy-three percent of Male Groups (designated prior to chase) contained exclusively adult males upon capture, whereas remaining “Male Groups” contained crias and/or adult females and crias. Forty-seven percent of Family Groups (designated prior to chase) contained 1 adult male, adult females, and the number of crias≤the number of adult females. Remaining Family Groups contained no or multiple adult males, and more crias than adult females. Average relatedness among all vicuñas was −0.007. Paternity analysis revealed that 35% of crias were captured with their biological mother and that only 1 cria was captured with both biological parents. Based on previous observations of group composition in the wild, animals from different groups may separate and/or mix during the chasing stage. Improvement of the chasing technique and instituting a post-capture monitoring program may aid in the detection of medium- and long-term impacts regarding group stability, cria survival, and ultimately wool production. [Copyright &y& Elsevier]

Selective breeding of the guanaco and vicuña indisputably led to the domestic llama and alpaca. However, the place, time and process of domestication remain poorly documented, exacerbated by increased evidence of historic and recent introgression among both domestic populations, especially those involving alpaca. Here, we report the first comprehensive assessment of patterns of microsatellite variation of 13 polymorphic microsatellites in 797 individuals representing 4 species and 2 subspecies to estimate historic and ongoing patterns of gene flow. Our results confirm that llamas were domesticated almost exclusively from the northern subspecies of guanaco (Lama guanicoe cacsilensis), but cluster analyses did not support previous findings that alpacas are solely derived from the northern subspecies of vicuña (Vicugna mensalis), with some more-recent admixture with southern populations. We also confirmed continued gene flow between llama and alpaca, and found evidence for crosses between presumably feral llamas and guanacos in northern Chile. Our results highlight the need to develop and test more-accurate markers and tools for assessing the genetic heritage of individuals, to link phenotypic variation with genetic ancestry, and to conserve historic patterns of unique variation among both the wild and domestic populations. • The dominant herbivores of the arid and semi-arid habitats of South America include wild and domestic species. • The genetic and phenotypic integrity of the domestic llama and alpaca are increasingly being threatened by interbreeding. • Loss of vicuña genetic signal in alpaca is due to hybridization and introgression among South American camelids. [ABSTRACT FROM AUTHOR]

Summary 1. The Chilean National Forestry and Park Service is striving to implement a guanaco management programme of sustained-yield use. To achieve this, the rate, variation and causes of juvenile guanaco mortality must be understood thoroughly. Therefore, we monitored the survival of 409 radio-collared juvenile guanacos in Torres del Paine National Park, Chile, from 1991 to 1996. 2. The Kaplan–Meier product limit estimator of survival for staggered entry was calculated, and survival rates between juvenile males and females and among years were compared using the lifetest procedure in SAS. The Cox proportional hazards model was used to relate mortality rate to explanatory variables such as juvenile sex, birth weight, adult female aggression towards researchers during the capture and tagging of newborns, population density, and mean monthly winter snowfall. 3. Mean juvenile survival rate (ŝ) was 0·38, but varied between 0·31 and 0·55. Survival rates between the sexes were not significantly different, although male survival was lower than that of females. Mortality rate was highest during the first 14 days after birth. Most deaths occurred between birth and 7 months of age. 4. The risk of mortality increased by almost 6% with every 1 cm increase in winter snowfall, whereas the risk of mortality decreased by almost 24% as adult female aggression increased towards researchers. 5. Current management objectives are aimed at the implementation of a rational harvest of guanacos on the Chilean side of the island of Tierra del Fuego. Our results provide improved and updated estimates of juvenile guanaco survival and will aid in the modelling of harvest rates of guanacos in southern Chile. Future proposed harvests from wild populations in southern Chile need to consider the rate and variation of this critical life-history parameter. [ABSTRACT FROM AUTHOR]